Hike This Active Volcano Before Dawn to See Its Electric Blue Flames Light up the Sky

There’s beauty and madness in hiking in the dark: beauty because you are free from seeing, literally, the difficulty ahead — and madness because you can’t spot your foot let alone your next step. Yet, on a recent pitch-black morning, that’s the juxtaposition my husband and I faced as we scaled the side of Kawah Ijen, an active volcano in Indonesia’s East Java that soars some 9,100 feet into the air, with a crystal-blue sulfuric lake smack in the center of its 2,369-foot-wide crater.

As we started on the steep path from the parking lot, a single dim headlamp between us, I turned to my husband and whined, “This better be worth it.”

There were points along the path — which, by Indonesian standards, was quite safe — that I thought I might quit. That I needed to quit. I stumbled in the dark, and lost my breath more often than I caught it. I even begged my husband to go ahead of me to spare me the shame of struggling so much to ascend to the summit of this massive mountain that I couldn’t see.

Sulfur miners, who handily walk the same path every morning before sunrise to scour the lake for hunks of sulfur, passed me on their way down. Some pointed and laughed at my exhaustion. I considered turning around, embarrassed and at times questioning my sanity.

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Then, the sunrise peeked out from behind two nearby mountains, and a pink line, straight as a ruler, reached out across their peaks. Above that line, the trees shimmered in fuchsia light; below it, they remained cast in complete darkness. It was the most beautiful sunrise I had ever seen, and in that light I found my way to the top.

I rounded a bend and the thick clouds — paired with the pungent smell of sulfuric acid — hit me before I could make out the drop of the crater’s rim. But there it was: a jagged, 660-foot-deep pit, with a still pool of water the color of a White Walker’s ice-blue eyes. With a sulfuric acid concentration of 0.13, the lake is too treacherous to touch or to sail, but from above, perched uncomfortably on the edge of a white-washed, sandy rock, the lake looks serene, as if an idyllic afternoon could be spent on its calm waters, in the safety of a canoe.

In the light of the sun — or perhaps in the intoxication of the sulfur fumes — I came to see the trek not as treacherous but as thrilling.

Less than 24 hours before, my husband and I had ascended to the rim of another active volcano: Mount Bromo, a 7,641-foot-tall crater in the center of what the Indonesians call Lautan Pasir, or “Sea of Sand.” Indeed, the flat plain on which our jeep parked was a desert in the middle of the lush jungle that is Java, so gritty and windy it was almost alien-like. From there, we hiked up a feeble staircase to the top of the mountain, where a knee-high railing separated us from the black lava bubbling below. Mount Bromo last erupted in 2015, closing climbing; Ijen has remained quiet since 1999.

There, the path around the rim was, at some points, just a foot wide, with two-way traffic — eager Instagrammers angling for a shot among more experienced hikers — making the trail feel even thinner, more dangerous, despite the daylight. The railing protected us from the lava, but left us exposed to the backside of the rocky mountain, just a single misstep to a quick but surely painful death. Ijen, then, by comparison, was more much peaceful and calming.

Back on Ijen’s rim, I turned to my husband. “This was worth it,” I said. “It really, really was.”